Depth Rating for Potted Cable Penetrator

Hello! Am trying to create a burn wire system for a deep sea drop camera and was wondering if the old potted cable penetrators are depth rated to 500m? I understand that the WetLink penetrators are depth rated to 950m but would like to see what the other options are. Thanks everyone.

Hi @Tides,

Due to the fickle nature of chemical reactions in a variable world, we can’t meaningfully provide an official depth rating for a general-purpose and user-sealed product like a potted penetrator. The depth capacity is dependent on the interface strengths between the potting compound, the cable jacket, and the aluminium walls of the penetrator, which depends on a variety of factors, including

  • the materials involved, and their chemical compatibilities
  • surface treatment of the cable jacket and penetrator wall
  • impurities, dirt, skin oils, etc that reduce bond strength
  • temperature and pressure during potting and setting (bubbles?)
  • correct seating of cable jacket against penetrator shoulder
  • length of bond
    • e.g. does the potting compound fill the head and extend into the throat?

It’s also relevant to consider storage and operating conditions, whereby

  • high temperatures (e.g. from extended direct sunlight exposure, or hot water) can degrade/weaken potting compound, and may cause thermal stresses from uneven expansion
  • strong jerks on the cable may shear the seal
  • if a non water-blocked cable gets cut, water can enter through the cable (true of any penetrator)

For reference,

It’s not impossible for a potted penetrator to withstand significant depths, but unfortunately it’s difficult to ascertain the depth capacity of a given potting without highly controlled installation and operating conditions, or actually testing it.